Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Animal Studies
Animal studies involving horses encompass a range of research focused on understanding equine biology, behavior, and health. These studies often investigate various aspects of horse physiology, genetics, nutrition, and disease pathology. Researchers utilize animal studies to explore the effects of different treatments, management practices, and environmental factors on horse welfare and performance. The findings from such studies contribute to the development of improved care strategies and health interventions. This page gathers peer-reviewed research studies and scholarly articles that explore the methodologies, findings, and implications of animal studies conducted on horses, providing insights into their application in advancing equine science.
Common and species-specific esterases of Equidae–IV. Horse of przewalski, onager and Zebra hartmannae. 1. Among several species of Equidae only E. przewalskii possesses a serum esterase identical with that of E. caballus. 2. The esterases of Hemionidae differ slightly from that of domestic horse by electrophoretic migration and by antigenic structure. 3. Zebras (grevyi, burchelli) appear devoid of this component but Z. hartmannae possesses an esterase of high enzymatic activity, differing notably from that of horse by electrophoretic and antigenic properties.
Comparative studies on blood serum alpha-L-fucosidases from several mammalian species. 1. Peripheral blood serum alpha-L-fucosidases have been studied from various mammalian species: Sus scropha var domestica L. (pig), Capra hircus L. (goat), Bos taurus L. (bull, races Morucha and Charolais), Equus caballus L. (horse) and Equus asinus L. (donkey). 2. Fluorimetric and spectrophotometric procedures were used for determination of alpha-L-fucosidases. 3. alpha-L-Fucosidases were more active towards fluorescent substrates than towards chromogenic substrates. 4. pH optima values of the enzymes are: (A) 5.5 for sera from all above-mentioned species when fluorescent substrates were empl...
Genetic polymorphism of the vitamin D binding protein and another post-albumin protein in horse serum. Horizontal polyacrylamide gel electrophoreses, on 10% separation gel, of horse serum revealed polymorphism of the vitamin D binding protein (Gc protein) and another post-albumin protein (Pa). Family data supported the hypothesis that Gc and Pa types were controlled by autosomal codominant alleles. For both Gc and Pa proteins, the homozygous types showed a single fraction while the heterozygous type had two fractions. Pa types were found to be identical to the post-albumin types reported earlier by starch gel electrophoresis. Two Gc alleles, GcF and GcS, and three Pa alleles, Pa D, Pa F and Pa ...
Bending properties of cortical bone of the horse. Bending properties of samples of cortical bone taken from the cranial, caudal, medial, and lateral quadrants of the midshaft of the radius, femur, and metacarpus of 12 ponies, 18 months old, were determined by 4-point loading at a rate of 10 mm/minute. The elastic modulus for all samples was between 16.2 and 20.2 GN/m2, and the ultimate breaking strength, between 204 and 255 MN/m2. There was greater variation in these properties between bone quadrants than between bones. Samples from the cranial and medial quadrants of both femur and radius were stiffer and had greater ultimate breaking streng...
A survey of biting flies attacking equines in three states of the southwestern United States, 1972. A survey of biting flies in the southwestern United States resulted in the recovery of 34 species as they attacked equines. The geographic distribution of each species at 15 sites and the abundance of attacking flies were used to determine that 22 species commonly attack equines. Culicoides variipennis (Coquillett) was the most common species collected; it was recovered at 12 sites and comprised the highest percentage (29.8%) of the total survey catch for all species collected. The next 2 most common species were Psorophora columbiae (Dyar & Knab) and Aedes vexans (Meigen). C. variipennis was ...
Germ cell proliferations in the fetal horse ovary. During the 340 day pregnancy of the horse, the germ cells in the fetal ovary showed a meiotic prophase which began in days 60-70 and might be prolonged after day 200. Three or four successive oogonial mitotic proliferations passed into the meiotic prophase but the great majority of the oocytes first involved degenerated, and no appreciable numbers of primordial follicles were left behind. At 150 days of pregnancy and again at 197 days, oocytes in early meiotic stages filled the ovarian cortex. Primordial follicles were present, but rare. As the prophase gradually came to an end, groups of oocy...
Some unusual cases of abnormal respiratory noises in the horse. Any condition which leads to a diminution in the size or alteration of the shape of the lumen of the respiratory tract in the horse may result in the production of abnormal respiratory noises at exercise.
Regional blood flow to the stomach and small intestine in ponies. Studies on regional blood flow to the stomach and small intestine were performed in 9 anesthetized ponies. Carbonized microspheres (15 +/- 5 micron in diameter) labeled with 85Sr were injected into the left atrium to determine blood flow distribution. In 4 ponies, the regional flows to mucosal-submucosal layers of the stomach and the small intestine were also measured. The nonglandular region of the stomach received the least blood per 100 g of tissue, and the duodenum received the greatest. The regional blood flow to the duodenum was significantly higher than that to the glandular stomach reg...
Ultrastructural observations suggesting merocrine secretion in the initial segment of the mammalian epididymis. Principal cells in the initial segment of the epididymis in horses, cattle, pigs, sheep, dogs, cats, and rabbits have an abundant, partly rough, endoplasmic reticulum and a large Golgi complex. Small vacuoles with opaque content seem to be formed by the Golgi complex and move to the cell apex, where they empty their contents into the lumen by a merocrine mechanism.
A subunit-sized butyrylcholinesterase present in high concentrations in pooled rabbit serum. A butyrylcholinesterase of mol.wt. approx. 83000 was observed in pooled rabbit serum. The enzyme was named monomeric butyrylcholinesterase to distinguish it from the larger oligomeric butyrylcholinesterase of horse and human serum whose subunits are the same size as the monomeric enzyme. The active-site concentration of monomeric butyrylcholinesterase in the pooled serum was 0.18mum, which is five times the concentration of butyrylcholinesterase in pooled horse serum. This was surprising, since the horse serum is regarded as a rich source of butyrylcholinesterase, whereas rabbit serum is not g...
Vasculature of the equine and canine iris. Methyl methacrylic casts were prepared and tissue was freshly collected for histologic examination to compare the vascular supply and the structure of the vessels of the iris in the adult horse with those of the dog. In the horse, ciliary blood vessels divided in the iris and formed a complete major arterial circle of the iris. In the dog, the ciliary blood vessels divided in the ciliary body and, by means of recurrent branches, formed a complete arterial circle. From this circle, radial arteries extended toward the pupillary margin. The radial vessels in the horse were nearly straight and joi...
Erythrocyte rosette formation of equine peripheral blood lymphocytes. Erythrocyte rosette (ER) formation of equine peripheral blood lymphocytes (PBL) was characterized. Guinea pig and, to a lesser extent, human erythrocytes formed ER; cat, cow, dog, hamster, mouse, rat, and sheep erythrocytes showed negligible rosetting properties. Conditions of the assay were varied to determine which procedure allowed the largest percentage of rosette formation. The PBL from 20 normal horses were then assayed, averaging 38 +/- 2% ER. To characterize the erythrocyte receptor as being on T or B cells, equine thymocytes from 6 foals were assayed; the thymocytes formed an average ...
Studies related to the metabolism of anabolic steroids in the horse: 19-nortestosterone. 1. The metabolism of 19-nortestosterone in a cross-bred horse has been studied using 14C-labelled material. 2. Two neutral metabolites isolated from urinary extracts by column chromatography were identified as isomers of 3-hydroxyestran-17-one and estrane-3,17-diol by g.l.c.-mass spectrometry. 3. The stereochemistry of the two metabolites has been investigated by comparison of the retention times of their trimethylsilyl derivatives with those of standard steroids of known configuration.
Staining of glycosaminoglycans in intervertebral disc cells. Disc material from horse, ox, sheep, pig, dog and cat was stained by the Alcian-blue-critical electrolyte concentration technique and with the standard and two-step periodic acid Schiff methods. The effects of pretreatment with hyaluronidase and with chondroitinase was also evaluated. There appears to be a small increase in total cellular glycosaminoglycan content with age in all species: cellular material of high molecular weight however only increases in aged animals. The degree of sulphation of cellular glycosaminoglycans does not vary with age or with position in the disc.
[The arterial vessels and their intraosseous course in the leg bones of foals. II. Humerus]. The arterial blood vessels in 24 humeri of equine fetusses and foals are described. The relation between the age and the distribution of these arteries are explained and completely discussed.
[Phantoms for the collection of genital secretions in stallions]. Practical experiences of the phantom method for collection of genital secretions from stallions are reported. Taking a phantom used in the Richard-Götze-Haus Tierärztliche Hochschule Hannover as a prototype two further models slightly modified have been constructed, baring a flat hollow in the right side of the caudal phantom body for manual inserting of the Artificial Vagina. These three models fulfill four important conditions for routine use: (1) sufficient sexual attractivity for the stallions; 80-85% successful collections of presecretions out of a total of 1050 using the dummy and 70% ...
Telemetric measurements of strain in the metacarpus of the horse: a pilot study. The advances made by the use of a telemetric system in the study of bone strain in a free-moving horse are reported. A rosette strain gauge was bonded to the craniomedial aspect of the metacarpus of the horse. Attachment of a miniature FM transmitter to lead wires facilitated telemetric transmission of of resistance changes which corresponded to limb movement. During 3 different gaits, the trace pattern remained similar, although frequency and amplitude varied. The tracings were similar to those reported in other species in which nontelemetric transmission was used.
An experimental study of autologous digital tendon transplants in the horse. Four autologous tendon grafting techniques, bipedicle, pedicle and free grafts of the deep digital flexor tendon and free grafts from the lateral digital extensor tendon were described. The vascularization and remodelling of the transplant and the reactions in the donor, as well as the recipient tendon, were studied by means of microangiographic and histochemical methods. The results indicated that regardless of the technique used the grafts were revascularized and replaced by a highly orientated and organized tendon. The use of free grafts may therefore be worthwhile in treatment of severe te...
[Experimental infection of horses with Fasciola hepatica]. Ten pony foals were infected with Fasciola hepatica; five animals received up to 1000 metacercariae orally, the remaining animals received up to 80 specimens of 24 hours old adulescariae intraperitoneally. The rate of development of the parasites varied in a wide range between 0,2 and 41%. Most of the liverflukes were found in animals severely infected with strongyles in the same time. Only 22 weeks after oral infection, the flukes had reached a length of 20 mm and sexual maturity. Fasciola-eggs could not be detected in the feces.
Horner’s syndrome in large animals. The sympathetic nervous innervation of the head was surgically transected in the horse, cow, sheep and goat. The site of transection was preganglionic in all 4 species and ganglionic-postganglionic in 2 additional horses. The Horner's syndrome, manifested as a result of the iatrogenic lesion, varied with the species. Ptosis was the most constant sign in all species. Unilateral sweating over the face and proximal neck, particularly at the base of the ear, was the most prominent feature in the horse. The cow revealed distension of vasculature and cutaneous heat of the pinna, and a reduced produc...
Studies on left ventricular isotonic function in conscious and anaesthetized ponies. The effects of thiopentone-halothane and thiopentone-ether anaesthesia on left ventricular isotonic function were assessed in Welsh Mountain ponies from measurements of left ventricular stroke work, minute work, stroke power, mean ejection rate and tension-time index.
All of these variables were affected similarly during anaesthesia, an initial marked reduction being followed by a progressive return towards control levels in the later stages of anaesthesia. Quantitative differences between the effects of each agent were evident, the depression which occurred during halothane anaesthesia bei...
Identification of the receptor involved in adrenaline mediated sweating in the horse. Using adrenergic agonists and antagonists this study has demonstrated that adrenaline induced sweating is mediated via beta2-adrenoreceptors in the horse.
